CN111585752B - A Semi-Quantum Dialogue Method Based on Identity Authentication - Google Patents

Abstract

The invention discloses a semi-quantum dialogue method based on identity authentication. First, the quantum party and the classical party share a random binary string in advance, and then the quantum party prepares qubits, and then passes the quantum party's identity sequence and secret information to the classical party through the qubits. Then the classical party performs identity authentication on the sent identity sequence and secret message, and then encodes and security checks the classical party’s identity sequence and secret message, and feeds it back to the quantum party; finally, the quantum party accepts the feedback information and The identity of the classical party is authenticated, and then the security of the channel is checked. Finally, the quantum party and the classical party decode each other’s secret message respectively, using a single photon source and a single photon detector. The technology is relatively mature, and the implementation of the classical party does not need to use Quantum registers. Identity authentication enables this protocol to effectively resist malicious attacks such as man-in-the-middle attacks and imitation attacks.

Description

A Semi-Quantum Dialogue Method Based on Identity Authentication

technical field

The invention belongs to the technical field of quantum secret communication, and relates to a semi-quantum dialogue method based on identity authentication.

Background technique

In recent years, quantum computing has posed a huge threat to traditional cryptography based on computational complexity with its super computing power. At the same time, quantum cryptography uses the principles of quantum mechanics to achieve theoretically unconditional secure communication. Since its inception, quantum cryptography has attracted extensive research by researchers both theoretically and experimentally, and has produced many interesting branches, such as quantum key distribution (Quantum key distribution, QKD) [1-4], quantum secret sharing (quantum secretsharing, QSS) [5-7], quantum secure direct communication (Quantum secure direct communication, QSDC) [8-10], quantum identity authentication (Quantum Identity Authentication, QIA) [11-13], etc.

QKD aims to establish a string of random keys between two remote communicators through quantum signal transmission. The difference between QSDC and QKD is that in the communication process of QSDC, the two parties do not need to generate keys in advance, but communicate by directly establishing a quantum channel to directly complete the secure transmission of secret messages. Since QSDC was proposed, QSDC protocols based on different quantum resources have been proposed [8-10,14,15], and related experiments have been proved [16-18]. With the development of QSDC, Nguyen et al first proposed a two-way QSDC protocol [19] in 2004, in which the sender and receiver can exchange their secret messages at the same time, so this protocol is also called quantum dialogue (Quantum Dialogue). Dialogue, QD). Since then, QD has attracted extensive research by domestic and foreign scholars. Unfortunately, in 2008, Tan et al. [20] and Gao et al. [21] pointed out that early QD protocols [19, 22–27] suffer from problems such as “classical correlation” or “information leakage”, that is, Any eavesdropper can extract information about transmitted secret messages from legitimate users' classical communications. In view of this, scholars have proposed many QD protocols that can overcome the problems of "classical correlation" or "information leakage" [28-46]. It is worth noting that quantum identity authentication (QIA) is an important topic of QD. Both parties in communication can verify the identity of each other through quantum identity authentication, so as to effectively resist problems such as man-in-the-middle attacks and imitation attacks in the communication process, and improve the security of the protocol. sex. In view of this, many QD protocols with identity authentication functions have also been proposed [32,35,37,40,43,46-48].

In order to realize the quantum cryptography protocol, it is worth considering to save the quantum resources and classical resources used in the quantum cryptography protocol. In the early practical quantum network, not every participant may have expensive quantum resources and skilled quantum state manipulation techniques. Based on this fact, in 2007, Boyer et al. [49] proposed a novel idea (i.e., the BKM2007 protocol) to reduce the quantum power of one of the participants. Since the operation done by the receiver in the whole protocol is similar to the classical operation, the protocol is also called the Semiquantum Key Distribution (SQKD) protocol, the receiver is called the "classical party", and the Z base is called Classic base. In 2009, Boyer et al. extended the original semi-quantum key distribution protocol [50] with measurement retransmission and randomization strategies. Since then, various SQKD protocols have been proposed [51-55]. In addition to SQKD, half-quantum ideas have also been applied to other half-quantum secure communication protocols, such as half-quantum secret sharing [56-59], half-quantum information partitioning [60], half-quantum private comparison [61], half-quantum Identity authentication [62,63], semi-quantum secure direct communication [41,64-68] and semi-quantum dialogue [41-43], etc.;

In terms of semi-quantum dialogue, Shukla et al. [41] proposed the first SQD protocol based on the Bell state in 2017. In 2018 Ye et al. [42] proposed a single-photon-based SQD protocol. In the same year, Liu et al. [43] proposed an SQD protocol with identity authentication function based on logical qubits. Two classical players of the protocol can exchange messages in a noisy environment by entrusting quantum computing to a quantum player. In the above three semi-quantum dialogue protocols, the classical party needs to have the ability to store qubits, that is to say, quantum memory is essential for classical players, which is very challenging for them in real life . In view of the above problems, the present invention proposes a semi-quantum dialogue method based on identity authentication, in which the classical party does not need to use quantum storage, which simplifies the realization of communication. At the same time, it has identity authentication and message authentication functions, which can resist man-in-the-middle attacks and ensure the integrity of messages.

Contents of the invention

The purpose of the present invention is to provide a method of semi-quantum dialogue based on identity authentication, to realize two-way communication and authentication between the quantum party and the classical party.

The technical solution adopted in the present invention is a method of semi-quantum dialogue based on identity authentication, which specifically includes the following steps:

Step 1, the quantum party and the classical party share a random binary string in advance, then the quantum party prepares qubits, and then sends the quantum party’s identity sequence and secret message to the classical party through the qubits;

Step 2, the classical party authenticates the identity sequence and secret message sent in step 1, and then encodes the classical party’s identity sequence and secret message and performs security checks, and feeds back to the quantum party;

In step 3, the quantum party accepts the information fed back in step 2, authenticates the identity of the classical party, and then checks the security of the channel. Finally, the quantum party and the classical party decode each other’s secret message respectively.

The present invention is also characterized in that:

Wherein the specific implementation of step 1 comprises the following steps:

Step 1.1, the quantum side and the classical side share a random binary string in advance, and then the quantum side prepares qubits;

Step 1.2, classifying the qubits prepared in step 1;

In step 1.3, the quantum party sends the identity sequence and secret message in combination with the qubits classified in step 1.2;

Wherein the random binary string in step 1.1 is K={k ₁ ,k ₂ ,...,k _2L }, wherein L=2(n+l)(1+δ), n is the length of ID _A and ID _B , ID _A is the identity sequence of the classical party, ID _B is the identity sequence of the quantum party, ID _A ＝{a ₁ ,a ₂ ,…,a _n }, ID _B ＝{b ₁ ,b ₂ ,…,b _n }, where a _i , b _i ∈ {0,1}, i ∈ {1,2,...,n};

δ>0是一个固定的参数；l is the length of M _A and M _B , M _A is the secret message of the classical party, M _B is the secret message of the quantum party,

δ>0 is a fixed parameter;

Wherein step 1.1 in quantum square preparation qubit specific content is:

The quantum square prepares L=2(n+l)(1+δ) single photons to form a sequence A according to K, if (k _2i-1 ,k _2i )=(0,0), the quantum square prepares |0> as a sequence The i-th qubit of A; if (k _2i-1 ,k _2i )=(0,1), the quantum square prepares |1> as the i-th qubit of sequence A; if (k _2i-1 ,k _2i )=(1,0), quantum square preparation|+>as the i-th qubit of sequence A; if (k _2i-1 ,k _2i )=(1,1), quantum square preparation|->as sequence A The i-th qubit; where i∈(1,2,…,L); Finally, the sequence A is divided into two subsequences A _Z and A _X , where A _Z represents all |0> and |1 in the sequence A > A _X denotes all |+> and |-> in the sequence A, where |A _Z |>(n+l);

和

划分方法为A_Z的第奇数个量子比特划分到集合

为AUTH量子比特，用于编码经典方和量子方的身份序列ID_A和ID_B；第偶数个量子比特划分到集合

为ENCODE量子比特，用于编码经典方和量子方的秘密消息M_A和M_B；The specific content of the classification of qubits in step 1.2 is: divide the first (n+l) qubits of A _Z into two sets

and

The division method is that the odd-numbered qubits of A _Z are divided into sets

It is the AUTH qubit, which is used to encode the identity sequences ID _A and ID _B of the classical party and the quantum party; the even numbered qubits are divided into sets

is the ENCODE qubit, used to encode the secret messages M _A and M _B of the classical party and the quantum party;

将A_X标注为

和

统称为CTRL量子比特，用于检测量子通道的安全性；The quantum square defines the remaining qubits in _Az as

label A _X as

and

Collectively referred to as CTRL qubits, they are used to detect the security of quantum channels;

中编码他的身份序列ID_B，若b_i＝0，搁置，若b_i＝1，量子方将量子比特翻转，即量子方将

中的第i个量子比特制备为

量子方在

上编码秘密消息M_B，若

搁置，若

量子方将将量子比特翻转，即量子方将

中的第i个量子比特制备为

其中j是该量子比特在序列A中的位置；The specific content of step 1.3 is: the quantum square is in the set

Encode his identity sequence ID _B in it, if b _i =0, put it on hold, if b _i =1, the quantum party will flip the qubit, that is, the quantum party will

The i-th qubit in is prepared as

Quantum square in

Encode the secret message M _B above, if

on hold, if

The quantum party will flip the qubit, that is, the quantum party will

The i-th qubit in is prepared as

where j is the position of the qubit in sequence A;

The specific content of step 2 is:

检测

是否与相应位置上的ID_B和K相匹配，若错误率超过预先设定的阈值P_t，经典方终止协议；Step 2.1, the classical party measures each AUTH qubit, and the measurement result is recorded as

detection

Whether it matches the ID _B and K at the corresponding position, if the error rate exceeds the preset threshold P _t , the classic party terminates the agreement;

If the detection is normal, the classical party encodes the identity sequence ID _A on the result state after the detection, and then returns them to the quantum party;

若第i个ENCODE量子比特的测量结果

为|0>，测量结果表示为0，若第i个ENCODE量子比特的测量结果

为|1>，测量结果表示为1；然后经典方根据K和M_A制备新的ENCODE量子比特，即将第i个ENCODE量子比特制备为

其中j是该量子比特在A中的位置，经典方将ENCODE量子比特返回给量子方；Step 2.2, the classical party measures each ENCODE qubit, and records the measurement result as

If the measurement result of the i-th ENCODE qubit

is |0>, the measurement result is expressed as 0, if the measurement result of the i-th ENCODE qubit

is |1>, and the measurement result is expressed as 1; then the classical party prepares a new ENCODE qubit according to _K and MA, that is, the ith ENCODE qubit is prepared as

Where j is the position of the qubit in A, and the classical party returns the ENCODE qubit to the quantum party;

Step 2.3, the classical party reflects each CTRL qubit to the quantum party without modification;

The specific content of step 3 is:

和

将

与相应的ID_A和K进行比较，若错误率低于P_t，确认经典方的身份进行测量，否则，量子方终止协议，并以认证的经典信道公布错误信息；In step 3.1, the quantum party stores the qubits returned by the classical party in turn in the order of return, and then extracts the AUTH and CTRL qubits returned by the classical party and performs measurements on the basis of the prepared quantum state. The measurement results are expressed as

and

Will

Compare with the corresponding ID _A and K, if the error rate is lower than P _t , confirm the identity of the classical party for measurement, otherwise, the quantum party terminates the agreement and publishes the error information through the authenticated classical channel;

与K进行比较，如果错误率低于P_t，量子方确认信道安全进行下一步操作，否则，终止协议，以认证的经典信道公布错误信息；Similarly, will

Compared with K, if the error rate is lower than P _t , the quantum party confirms that the channel is safe and proceeds to the next step, otherwise, terminates the agreement and publishes the error information through the authenticated classical channel;

解码得到经典方要发送给他的消息，为

其中

经典方测量的ENCODE量子比特的第i个测量结果，j表示ENCODE量子比特在序列A中的位置，

为Bob发送给Alice的第i个秘密消息；Step 3.2, the quantum square uses K and

Decode to get the message that the classic party wants to send to him, as

in

The i-th measurement result of the ENCODE qubit measured by the classical method, j represents the position of the ENCODE qubit in sequence A,

is the ith secret message sent by Bob to Alice;

解码得到量子方要发送给她的消息

其中

为经典方测量的ENCODE量子比特的第i个测量结果；The classic formula uses K and

Decoded to get the message that the quantum party wants to send to her

in

is the i-th measurement result of the ENCODE qubit measured by the classical party;

In step 1, when the classical party receives the sequence code sent by the quantum party, a wavelength filter is placed in front of the qubit receiving device.

The beneficial effects of the present invention are:

The identity authentication-based semi-quantum dialogue method adopted in the present invention is realized by using a single-photon source and a single-photon detector, and the technology is relatively mature, and at the same time, the realization of the classical method does not need to use a quantum register. Identity authentication enables this protocol to effectively resist malicious attacks such as man-in-the-middle attacks and imitation attacks.

Description of drawings

Fig. 1 is a work flow diagram of the semi-quantum dialogue system based on identity authentication in the method of semi-quantum dialogue based on identity authentication of the present invention.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

和

Alice和Bob相互共享了各自的身份序列ID_A＝{a₁,a₂,…,a_n}和ID_B＝{b₁,b₂,…,b_n}，其中a_i,b_i∈{0,1}，i∈{1,2,…,n}；同时，Alice和Bob预先共享一个随机二进制串K＝{k₁,k₂,…,k_2L}，其中L＝2(n+l)(1+δ)，n是ID_A和ID_B的长度，l是M_A和M_B的长度，δ>0是一个固定的参数，假设量子信道是无损和无噪声的。The communication parties are the classical party Alice and the quantum party Bob, Alice and Bob want to use single photons to securely exchange each other's secret messages

and

Alice and Bob share their respective identity sequences ID _A ={a ₁ ,a ₂ ,…,a _n } and ID _B ={b ₁ ,b ₂ ,…,b _n }, where a _i , _bi ∈{ 0,1}, i∈{1,2,…,n}; meanwhile, Alice and Bob share a random binary string K={k ₁ ,k ₂ ,…,k _2L } in advance, where L=2(n+ l)(1+δ), n is the length of ID _A and ID _B , l is the length of _MA and _MB , δ>0 is a fixed parameter, assuming that the quantum channel is lossless and noise-free.

The present invention provides a method of semi-quantum dialogue based on identity authentication, as shown in Figure 1, specifically implemented according to the following steps:

Step 1, the quantum party and the classical party share a random binary string in advance, then the quantum party prepares qubits, and then sends the quantum party identity sequence and secret message to the classical party through the qubits:

In step 1.1, the quantum side and the classical side share a random binary string in advance, and then the quantum side prepares qubits:

The quantum square prepares L=2(n+l)(1+δ) single photons to form a sequence A according to K, if (k _2i-1 ,k _2i )=(0,0), the quantum square prepares |0> as a sequence The i-th qubit of A; if (k _2i-1 ,k _2i )=(0,1), the quantum square prepares |1> as the i-th qubit of sequence A; if (k _2i-1 ,k _2i )=(1,0), quantum square preparation|+>as the i-th qubit of sequence A; if (k _2i-1 ,k _2i )=(1,1), quantum square preparation|->as sequence A The i-th qubit; where i∈(1,2,…,L); Finally, the sequence A is divided into two subsequences A _Z and A _X , where A _Z represents all |0> and |1 in the sequence A > A _X denotes all |+> and |-> in the sequence A, where |A _Z |>(n+l);

Step 1.2, classifying the qubits prepared in step 1:

和

划分方法为A_Z的第奇数个量子比特划分到集合

为AUTH量子比特，用于编码经典方和量子方的身份序列ID_A和ID_B；第偶数个量子比特划分到集合

为ENCODE量子比特，用于编码经典方和量子方的秘密消息M_A和M_B；直至一个集合满了，剩余的量子比特全部划分到另外一个集合中Divide the first (n+l) qubits of A _Z into two sets

and

The division method is that the odd-numbered qubits of A _Z are divided into sets

It is the AUTH qubit, which is used to encode the identity sequences ID _A and ID _B of the classical party and the quantum party; the even numbered qubits are divided into sets

It is the ENCODE qubit, which is used to encode the secret messages _{MA and M B of} the classical party and the quantum party; until one set is full, the remaining qubits are all divided into another set

将A_X标注为

和

统称为CTRL量子比特，用于检测量子通道的安全性。The quantum square defines the remaining qubits in _Az as

label A _X as

and

Collectively referred to as CTRL qubits, they are used to detect the security of quantum channels.

In step 1.3, the quantum party sends the identity sequence and secret message combined with the qubits classified in step 1.2:

中编码他的身份序列ID_B，若b_i＝0，搁置不操作，若b_i＝1，量子方将量子比特翻转(将K和ID_B结合起来可以直接在步骤1.1中生成这些量子比特)，即量子方将

中的第i个量子比特制备为

量子方在

上编码秘密消息M_B，若

搁置，若

量子方将将量子比特翻转(通过把K和M_B结合，也可以在步骤1.1中直接生成量子比特)，即量子方将

中的第i个量子比特制备为

其中j是该量子比特在序列A中的位置；Quantum square in the assembly

Encode his identity sequence ID _B in , if b _i =0, put it on hold and do not operate, if b _i =1, the quantum party will flip the qubits (combining K and ID _B can directly generate these qubits in step 1.1) , that is, the quantum square will

The i-th qubit in is prepared as

Quantum square in

Encode the secret message M _B above, if

on hold, if

The quantum square will flip the qubit (by combining K and _MB , the qubit can also be generated directly in step 1.1), that is, the quantum square will

The i-th qubit in is prepared as

where j is the position of the qubit in sequence A;

Bob sends the sequence A to Alice, in order to prevent the Trojan horse attack, Alice needs to place a wavelength filter in front of her qubit receiving device;

上进行身份认证，在

上进行消息编码，在剩下的

和

上进行安全检测，具体内容如下：In step 2, the classical party authenticates the identity sequence and secret message sent in step 1, then encodes and performs security checks on the identity sequence and secret message of the classical party, and feeds back to the quantum party. For each arriving qubit, Alice is in

Authenticate on the

message encoding on the

and

Perform security checks on the Internet, the details are as follows:

检测

是否与相应位置上的ID_B和K相匹配，若错误率超过预先设定的阈值P_t，经典方终止协议；Step 2.1, the classical party measures each AUTH qubit, and the measurement result is recorded as

detection

Whether it matches the ID _B and K at the corresponding position, if the error rate exceeds the preset threshold P _t , the classic party terminates the agreement;

If the detection is normal, the classical party encodes the identity sequence ID _A on the result state after the detection, and then returns them to the quantum party;

若第i个ENCODE量子比特的测量结果

为|0>，测量结果表示为0，若第i个ENCODE量子比特的测量结果

为|1>，测量结果表示为1，在测量完第i个ENCODE量子比特之后，经典方根据K和M_A制备新的ENCODE量子比特，即将第i个ENCODE量子比特制备为

其中j是该量子比特在A中的位置，经典方将ENCODE量子比特返回给量子方；Step 2.2, the classical party measures each ENCODE qubit, and records the measurement result as

If the measurement result of the i-th ENCODE qubit

is |0>, the measurement result is expressed as 0, if the measurement result of the i-th ENCODE qubit

is |1>, the measurement result is expressed as 1, after measuring the i-th ENCODE qubit, the classical method prepares a new ENCODE qubit according to _K and MA, that is, the i-th ENCODE qubit is prepared as

Where j is the position of the qubit in A, and the classical party returns the ENCODE qubit to the quantum party;

Step 2.3, the classical party reflects each CTRL qubit to the quantum party without modification;

In step 3, the quantum party accepts the information fed back in step 2, authenticates the identity of the classical party, and then checks the security of the channel. Finally, the quantum party and the classical party decode each other’s secret message respectively. The details are as follows:

和

将

与相应的ID_A和K进行比较，若错误率低于P_t，确认经典方的身份进行测量，否则，量子方终止协议，并以认证的经典信道公布错误信息，返回第一步；In step 3.1, the quantum party stores the qubits returned by the classical party in turn in the order of return, and then extracts the AUTH and CTRL qubits returned by the classical party and performs measurements on the basis of the prepared quantum state. The measurement results are expressed as

and

Will

Compare with the corresponding ID _A and K, if the error rate is lower than P _t , confirm the identity of the classical party for measurement, otherwise, the quantum party terminates the agreement, and publishes the error information through the authenticated classical channel, and returns to the first step;

与K进行比较，如果错误率低于P_t，量子方确认信道安全进行下一步操作，否则，终止协议，以认证的经典信道公布错误信息，返回第一步；Similarly, will

Compared with K, if the error rate is lower than P _t , the quantum party confirms that the channel is safe and proceeds to the next step, otherwise, terminates the agreement, publishes the error message through the authenticated classical channel, and returns to the first step;

解码得到经典方要发送给他的消息，为

其中

经典方测量的ENCODE量子比特的第i个测量结果，j表示ENCODE量子比特在序列A中的位置，

为Bob发送给Alice的第i个秘密消息；Step 3.2, the quantum square uses K and

Decode to get the message that the classic party wants to send to him, as

in

The i-th measurement result of the ENCODE qubit measured by the classical method, j represents the position of the ENCODE qubit in sequence A,

is the ith secret message sent by Bob to Alice;

解码得到量子方要发送给她的消息

其中

为经典方测量的ENCODE量子比特的第i个测量结果。The classic formula uses K and

Decoded to get the message that the quantum party wants to send to her

in

is the i-th measurement result of the ENCODE qubit measured by the classical party.

Claims (1)

1. A method of semi-quantum conversation based on identity authentication is characterized by comprising the following steps:

step 1, a quantum party and a classical party share a random binary string in advance, then the quantum party prepares a quantum bit, then a quantum party identity sequence and a secret message are sent to the classical party through the quantum bit, and when the classical party receives a sequence code sent by the quantum party, a wavelength filter is placed in front of a quantum bit receiving device, wherein the specific implementation mode comprises the following steps:

step 1.1, a quantum party and a classical party share a random binary string in advance, and then the quantum party prepares a quantum bit; random binary string of K = { K = ₁ ,k ₂ ,…,k _2L Where L =2 (n + L) (1 + δ), n is ID _A And ID _B Length, ID of _A Is a classical square identity sequence, ID _B Is a quantum square identity sequence, ID _A ＝{a ₁ ,a ₂ ,…,a _n }，ID _B ＝{b ₁ ,b ₂ ,…,b _n In which a is _i ,b _i ∈{0,1},i∈{1,2,…,n}；

l is M _A And M _B Length of (C), M _A Secret messages for classical parties, M _B Is a secret message of the quantum party,

δ>0 is a fixed parameter;

the specific content of the quantum bit prepared by the quantum method is as follows:

quantum method for preparing L =2 (n + L) (1 + delta) single photon composition sequence A according to K, if (K) _2i-1 ,k _2i ) = (0, 0), quantum-square preparation |0>The ith qubit as sequence A; if (k) _2i-1 ,k _2i ) = (0, 1), quantum method preparation |1>The ith qubit as sequence A; if (k) _2i-1 ,k _2i ) = (1, 0), quantum side preparation | +>The ith qubit as sequence A; if (k) _2i-1 ,k _2i ) =1, quantum preparation | ->The ith qubit as sequence A; wherein i ∈ (1, 2, \8230;, L); finally dividing the sequence A into two subsequences A _Z And A _X Wherein A is _Z Represents all |0 s in sequence A>And |1>；A _X Represents all | +in the sequence A>And | ->Wherein | A _Z |>(n+l)；

Step 1.2, the qubits prepared in step 1.1 are classified; the specific content of the classification of the qubits is as follows: a is to be _Z Is divided into two sets

And

the division method is A _Z Into a set

For AUTH qubits, for encoding the identity sequences ID of the classical party and the quantum party _A And ID _B (ii) a Dividing even numbered qubits into sets

For encodings of secret messages M of classical and quantum parties, for encodings of ENCODE qubits _A And M _B ；

Quantum prescription A _z The remaining qubits in is defined as

A is prepared from _X Is marked as

And

collectively known as CTRL qubits, for detecting the security of the quantum channel;

step 1.3, the quantum party sends the identity sequence and the secret message by combining the quantum bit classified in the step 1.2: quantum in set

Encodes his identity sequence ID _B If b is _i =0, rest, if b _i =1, quantum party will qubit flip, i.e. quantum party will

The ith qubit in (a) is prepared as

The quantum is as follows

Up-coding secret message M _B If, if

On the shelf, if

The quantum square will flip the qubit, i.e. the quantum square will

The ith qubit in (a) is prepared as

Where j is the position of the qubit in sequence A;

step 2, the classical party performs identity authentication on the identity sequence and the secret message sent in the step 1, then performs coding and security detection on the identity sequence and the secret message of the classical party, and feeds back the identity sequence and the secret message to the quantum party:

step 2.1, classical approachMeasuring each AUTH qubit, and recording the measurement result as

Detection of

Whether or not to correspond to the ID at the corresponding position _B Matching with K, if the error rate exceeds the preset threshold value P _t The classical party terminates the protocol;

if the detection is normal, the classical party codes the identity sequence ID on the detected result state _A Then return them to the quantum party;

step 2.2, the classical party measures each ENCODE qubit and records the measurement as

If the measurement result of the ith ENCODE qubit

(i) Is |0>The measurement result is expressed as 0 if the measurement result of the ith ENCODE qubit

(i) Is |1>The measurement result is represented as 1; then the classical party according to K and M _A Preparing new ENCODE qubit, i.e. preparing the ith ENCODE qubit as

Wherein j is the position of the qubit in A, the classical party returning the ENCODE qubit to the quantum party;

step 2.3, the classical party reflects each CTRL qubit to the quantum party without modification;

and 3, the quantum party receives the information fed back by the step 2, authenticates the identity of the classical party, detects the security of a channel, and finally decodes the secret message of the other party by the quantum party and the classical party respectively, which is implemented according to the following steps:

and 3.1, sequentially storing the qubits returned by the classical party by the quantum party according to the return sequence, extracting AUTH and CTRL qubits returned by the classical party, and measuring by the prepared quantum state basis, wherein the measurement results are respectively expressed as

And

will be provided with

With the corresponding ID _A Comparing with K, if the error rate is lower than P _t Confirming the identity of the classical party to measure, otherwise, the quantum party terminates the protocol and publishes error information by the authenticated classical channel;

in the same way, will

Comparing with K, if the error rate is lower than P _t The quantum side confirms that the channel is safe to carry out the next operation, otherwise, the protocol is terminated, and error information is published by the authenticated classical channel;

step 3.2, quantum square K and

decoding results in a message to be sent to him by the classical party, of

Wherein

The ith measurement of the ENCODE qubit, measured by the classical party, j representing the position of the ENCODE qubit in sequence a,

an ith secret message sent to Alice for Bob;

k for classical prescription and

decoding to obtain the message to be sent by the quantum party

Wherein

The ith measurement result of an ENCODE qubit measured for the classical party.

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